Oral Health and Systemic Diseases Research Group, University of Louisville School of Dentistry, Louisville, KY 40202, USA.
Biol Chem. 2012 Sep;393(9):971-7. doi: 10.1515/hsz-2012-0175.
RgpA and Kgp gingipains are non-covalent complexes of endoprotease catalytic and hemagglutinin-adhesin domains on the surface of Porphyromonas gingivalis. A motif conserved in each domain has been suggested to function as an oligomerization motif. We tested this hypothesis by mutating motif residues to hexahistidine or insertion of hexahistidine tag to disrupt the motif within the Kgp catalytic domain. All modifications led to the secretion of entire Kgp activity into the growth media, predominantly in a form without functional His-tag. This confirmed the role of the conserved motif in correct posttranslational proteolytic processing and assembly of the multidomain complexes.
RgpA 和 Kgp 牙龈蛋白酶是牙龈卟啉单胞菌表面内切蛋白酶催化结构域和血凝素-黏附结构域的非共价复合物。每个结构域中都有一个保守的基序,被认为是一个寡聚基序。我们通过将 motif 残基突变为六组氨酸或插入六组氨酸标签来破坏 Kgp 催化结构域中的 motif,从而验证了这一假设。所有的修饰都导致了完整的 Kgp 活性分泌到生长培养基中,主要是以没有功能 His 标签的形式。这证实了保守基序在正确的翻译后蛋白水解加工和多结构域复合物组装中的作用。